tractor/tests/test_child_manages_service_...

231 lines
5.7 KiB
Python

'''
Test a service style daemon that maintains a nursery for spawning
"remote async tasks" including both spawning other long living
sub-sub-actor daemons.
'''
from typing import Optional
import asyncio
from contextlib import asynccontextmanager as acm
import pytest
import trio
from trio_typing import TaskStatus
import tractor
from tractor import RemoteActorError
from async_generator import aclosing
async def aio_streamer(
from_trio: asyncio.Queue,
to_trio: trio.abc.SendChannel,
) -> trio.abc.ReceiveChannel:
# required first msg to sync caller
to_trio.send_nowait(None)
from itertools import cycle
for i in cycle(range(10)):
to_trio.send_nowait(i)
await asyncio.sleep(0.01)
async def trio_streamer():
from itertools import cycle
for i in cycle(range(10)):
yield i
await trio.sleep(0.01)
async def trio_sleep_and_err(delay: float = 0.5):
await trio.sleep(delay)
# name error
doggy() # noqa
_cached_stream: Optional[
trio.abc.ReceiveChannel
] = None
@acm
async def wrapper_mngr(
):
from tractor.trionics import broadcast_receiver
global _cached_stream
in_aio = tractor.current_actor().is_infected_aio()
if in_aio:
if _cached_stream:
from_aio = _cached_stream
# if we already have a cached feed deliver a rx side clone
# to consumer
async with broadcast_receiver(from_aio, 6) as from_aio:
yield from_aio
return
else:
async with tractor.to_asyncio.open_channel_from(
aio_streamer,
) as (first, from_aio):
assert not first
# cache it so next task uses broadcast receiver
_cached_stream = from_aio
yield from_aio
else:
async with aclosing(trio_streamer()) as stream:
# cache it so next task uses broadcast receiver
_cached_stream = stream
yield stream
_nursery: trio.Nursery = None
@tractor.context
async def trio_main(
ctx: tractor.Context,
):
# sync
await ctx.started()
# stash a "service nursery" as "actor local" (aka a Python global)
global _nursery
n = _nursery
assert n
async def consume_stream():
async with wrapper_mngr() as stream:
async for msg in stream:
print(msg)
# run 2 tasks to ensure broadcaster chan use
n.start_soon(consume_stream)
n.start_soon(consume_stream)
n.start_soon(trio_sleep_and_err)
await trio.sleep_forever()
@tractor.context
async def open_actor_local_nursery(
ctx: tractor.Context,
):
global _nursery
async with trio.open_nursery() as n:
_nursery = n
await ctx.started()
await trio.sleep(10)
# await trio.sleep(1)
# XXX: this causes the hang since
# the caller does not unblock from its own
# ``trio.sleep_forever()``.
# TODO: we need to test a simple ctx task starting remote tasks
# that error and then blocking on a ``Nursery.start()`` which
# never yields back.. aka a scenario where the
# ``tractor.context`` task IS NOT in the service n's cancel
# scope.
n.cancel_scope.cancel()
@pytest.mark.parametrize(
'asyncio_mode',
[True, False],
ids='asyncio_mode={}'.format,
)
def test_actor_managed_trio_nursery_task_error_cancels_aio(
asyncio_mode: bool,
arb_addr
):
'''
Verify that a ``trio`` nursery created managed in a child actor
correctly relays errors to the parent actor when one of its spawned
tasks errors even when running in infected asyncio mode and using
broadcast receivers for multi-task-per-actor subscription.
'''
async def main():
# cancel the nursery shortly after boot
async with tractor.open_nursery() as n:
p = await n.start_actor(
'nursery_mngr',
infect_asyncio=asyncio_mode,
enable_modules=[__name__],
)
async with (
p.open_context(open_actor_local_nursery) as (ctx, first),
p.open_context(trio_main) as (ctx, first),
):
await trio.sleep_forever()
with pytest.raises(RemoteActorError) as excinfo:
trio.run(main)
# verify boxed error
err = excinfo.value
assert isinstance(err.type(), NameError)
def test_stashed_child_nursery():
_child_nursery = None
async def waits_on_signal(
ev: trio.Event(),
task_status: TaskStatus[trio.Nursery] = trio.TASK_STATUS_IGNORED,
):
'''
Do some stuf, then signal other tasks, then yield back to "starter".
'''
await ev.wait()
task_status.started()
async def mk_child_nursery(
task_status: TaskStatus = trio.TASK_STATUS_IGNORED,
):
'''
Allocate a child sub-nursery and stash it as a global.
'''
nonlocal _child_nursery
async with trio.open_nursery() as cn:
_child_nursery = cn
task_status.started(cn)
# block until cancelled by parent.
await trio.sleep_forever()
async def sleep_and_err(ev: trio.Event):
await trio.sleep(0.5)
doggy() # noqa
ev.set()
async def main():
async with (
trio.open_nursery() as pn,
):
cn = await pn.start(mk_child_nursery)
assert cn
ev = trio.Event()
cn.start_soon(sleep_and_err, ev)
# this causes inf hang
await cn.start(waits_on_signal, ev)
# this does not.
# cn.start_soon(waits_on_signal, ev)
with pytest.raises(NameError):
trio.run(main)